Labeling an antibody with a specific tag has become an important and routine procedure in biological sciences and medical research. Tags, which range from visual markers such as fluorescent dyes to hapten molecules like biotin, can be used to enhance the visibility of immune complexes and protein-protein interactions or can be used in the isolation and purification of a protein.

When determining which type of label to choose, focus on the downstream application for which the antibody will be used. Fluorescent tags are used predominantly in cellular imaging, flow cytometry, fluorescent blotting, and immunofluorescence applications. In contrast, enzymatic tags, such as HRP and AP, are commonly used for blotting, ELISAs, and immunohistochemistry applications. Hapten tags such as biotin are the more versatile of the possible tag options as they can be used in protein isolation, purification, and any of the aforementioned applications.

AAT Bioquest offers a comprehensive suite of antibody and protein labeling kits to choose from. Designed for the novice scientist in mind, these kits have the easiest protocols and require the least hands-on experience.

AAT Bioquest ReadiLink™ Rapid Antibody Labeling Kits provide a quick and convenient method to label microscale volumes of antibodies with our superior iFluor^®dyes, mFluor™ dyes, or other labels. The unique chemistry of ReadiLink™ kits enables researchers to effortlessly label and recover 100% of their antibodies without a purification step. Since ReadiLink™ conjugates are covalently labeled, they are stable for long-term storage. They are ideal for demanding applications, including fluorescent microscopy, multi-color imaging, multiplex flow cytometry, primary detection, IHC, FISH, ELISAs, and more.

ReadiLink™ Rapid Antibody Labeling Kits utilize amine-reactive labels to prepare covalently labeled conjugates. These reactive labels selectively target and bind to primary amines, such as lysine residues, on the antibody of interest. To label your antibody, mix your antibody solution (concentration ~1 mg/mL) with the ReadiLink™ reaction buffer, add the mixture to the vial of pre-formulated label, and incubate for 30 to 60 minutes. Lastly, add the TQ™-Dyed Quench Buffer to your mixture and mix well. This part is key as it eliminates both background interference and the column purification step. After 10 minutes of incubation, your conjugates are ready to use.

ReadiLink™ xtra Rapid Antibody Labeling Kits with BSA compatibility takes labeling primary antibodies to a whole new level of convenience. Utilizing an optimized labeling protocol combined with vials of specially formulated labels, ReadiLink™ xtra kits enable rapid and reproducible labeling of microgram quantities of a primary antibody in the presence of common buffer additives and stabilizing proteins. In just two simple steps and without column purification, covalently label antibodies suitable for use in any immuno-based application.

Buccutite™ crosslinking technology offers a trouble-free way to covalently label proteins and antibodies with horseradish peroxidase (HRP), alkaline phosphatase (AP), or a phycobiliprotein. Compared to the conventional techniques for protein-protein conjugation, such as the SMCC chemical labeling method, Buccutite™ conjugation is significantly more robust and less demanding. These kits allow optimal labeling of microgram amounts of antibodies (as little as 25 µg per labeling reaction) in less than two hours, with no purification necessary and 100% yield. With Buccutite™ labeling kits, routinely prepare covalently-labeled conjugates that will withstand the rigorous washing techniques generally required in a typical immunoassay (e.g., ELISA, IHC, and Western blot) or flow cytometry application.